Signor of one-half to oliver t



(No Model.)

I. LA RUE JOHNSON. METHOD OF VENTILATING SUBWAYS.

im HI- 1..

'Patented Nov. 12, 1889.

UNITED ISTATES PATENTv OFFICE.

.'IsAAc'LA RUE JOHNSON, or WASHINGTON, DISTRICT or COLUMBIA, AS`

SIGNOR or ONE-HALF To OLIVER rr. THOMPSON, or SAME PLAOH.

METHOD OF VENTILATING SUVBWAYS.

SPECIFICATION forming part of Letters Patent No. 415,110, dated November12, 1889.'

' Y i Application led July 9, 18894 Serial No. 316,997. (No model.) i

To all whom it may concern: i

Be it known that I, ISAAC LA RUE JOHN- SON, a citizen of the UnitedStates, residing at Washington, in the District of Columbia,

have invented certain new and useful Improvements in the Method ofandMechanism for Ventilating Electric Subways'` and'Conduits; and I dohereby declare the'following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same.

My invention relates to impro\'fements in ventilation, whichimprovements are especially adapted to electrical conduits and subways,and has for its object the conveying away of gases, vapors, and moisturethat collect in lsuch subways, conduits, and their manholes, andprevention of the admission of the external air thereto, all of which isaccomplished by the method and mechanism for carrying out the same whichwill be hereinafter more fully set forth and described.

It consists in mechanism for and the method of Ventilating conduits andsubways by suitable mechanism connected with the lampmast of anelectric-light lamp, whereby the tubular form of said mast is madeavailable as an exhaust-pipe and as a conduit for conveying a current ofelectricity from the main conduit or subway to a motor for driving` asuitable exhaust-fan; and it further consists in so constructing andadjusting the exhaustfan as to prevent a downdraft through thelalnp-mast, thus preventing the admission of vthe external air throughsaid mast, which thereby prevents the discharge of the foul or damp airfrom the conduit, and thereby preventing explosions, which occur thereinwhen atmospheric air mingles with illuminating and other gases whichiind access to the conduits and their man-holes; and it further consistsin the means and mechan ism to be more particularly hereinafter setforth in this specification.

To enable others skilled in the art to understand my invention, I willnow proceed to a detailed description thereof in connection with theaccompanying drawings, in which- Figure 1'is an elevation, partly insection, showing a conduit of any improved pattern and the means ofconnecting-the conduit and the lamp-mast, a motor-case on said mast, andthe conductors leading from the cable in the conduit to theinterior ofthe mast and thence to the motor, and a hood or cowl is placed at thetop of the mast. Fig. 2 is a sectional elevation showin g theexhaust-fan and its motor.

Like reference-letters indicate corresponding parts in the severalfigures of the drawings, referring to which- A designates a form ofelectrical subway, preferably an improvement upon that which is shown inPatents Nos. 281,064 and 281,220, and which it is proposed shall formthe subj ectmatter of a separate application, it being shown here tomore fully illustrate the present invention. y

'a indicates the cables from a conductor, in

which the electric current is taken for driving the motor.

Bis the lamp-mast, tubular in form and having a tubular arm G, .to whichthe lamp is affixed.

C represents a preferred form of exhaustfan having the convolutions ofthe screw. This form of fan fits snugly in the bore of the mast, and asit moves in but one direction-4 that is, to exhaust-there can be nodowndraft through the mast to the conduit. The shaft of the fan isstepped in brackets or lugs c, that are affixed to or integral with thebore of the mast.

The motor and fan have suitable belt-andpulley connections with eachother, as indicated at d, though other means, as gearing and the like,may be employed.

E shows a case or housing for the motor, and F any desired form of lamp.

The prolongation of the bore of the tube is closed by acowl or hood H,which is suitably capped to prevent the ingress of moisture and isprovided with wings or blades 4against which the wind impinges to rotatethe same.

The operation of the mechanism will be readily understood. A suitablenumber of masts may be employed on a line of subway, such number andtheir dimensions according with the size, capacity, and configuration ofthe conduit. The conduit may be of any desired form, though the onepreferred is shown in the drawings. The pipe b, which connects IOO themast and conduit by suitable air and water tight joints, conveys thecurrent, (through suitable conductors) both for power and light from theconductor tothe lamp and motor. The case containing yhe motor isprovided with a door or opening through which the motors may be startedor stopped and through which they may be reached for repairs. The fan,having any number of spirals and of any desired pitch, is actuated bythe motor through the belt-and-pulley connections, as shown, and thisexhausts the air or gases in the mast, and its continued operationremoves all that may gather in the subway and its connections. It willbe perceived that the fan rotating continuously in one direction willnot permit the access of the external air by reason of the current whichit will of itself generate from the subway. The work of the fan will besupplemented by that of the hood, which will eject the foul air withoutpermitting the entrance of the external atmospheric air and therebycreating a downdraft, as both the reactionary effect of the outgoingcurrent and the impact of the outer air upon the blades of the hood willassure a ready exit of the former.

When it is desired to apply the mechanism and method herein set forth toVentilatingconduits for low-tension currents, tubes analogous to thelamp-masts are to be substituted therefor, only such parts beingldispensed with as are essential in electric lighting b means of themasts.

I do not limit myself to the mechanism above described, as modificationswill readily Suggest themselves, and of these I propose to avail myself.v l

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

l, A ventilator for conduits or subways, consisting of pipes or tubesconnecting the same with a lamp-mast or similar structure, saidlamp-mast containing an exhaust mechanism and a motor located thereonfor actuating said exhaust mechanism.

2. A ventilator for conduits or subways, which consists ina tubularconnection of the saine with a lamp-mast or similar tubular structure,and an exhaust mechanism located in said structure and actuated by amotor located upon said mast.

3. A ventilator for conduits or subways, comprising a tubular connectionof the same with a lamp-mast or similar structure, an exhaust-fan insaid mast, and an electric motor for actuating the fan.

4. In a ventilator for conduits or subways, the combination of a tubularlamp-mast, an exhaust-fan located therein, a motor located thereon foractuating said fan, and a rotary cowl or hood on said mast forpreventing a downdraft through said mast, and which by its rotary andreactionary motion ejects the air thrown up by the fan.

5. A lampmast having an exhaust-fan therein, an electric motor foractuating said fan, deriving its prime motor from the conduit or subwaywith which it is connected.

ISAAC LA RUE JOHNSON.

Witnesses:

BENJ. R. CATLIN, J. MAwDsLEY.

